Table 1 An illustrative example of temporal cluster construction, with a simulated set of 11 KD case onsets (second row) over a period of 25 consecutive days.

From: Author Correction: Clustering and climate associations of Kawasaki Disease in San Diego County suggest environmental triggers

Day # 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
# of KD Cases 2 2 1 0 0 0 0 0 1 0 0 0 0 0 2 1 1 1 1 0 0 0 0 0 1
Cluster Day? 1 1 1 1 1 1 1 0 0 0 0 1 1 1 1 1 1 1 1 1 1 0 0 0 0
Cluster KD Day? C C C       NC       C C C C C       NC
Cluster Size 5 cases      6 cases     
  1. By our definitions, this would be coded as 2 temporal clusters (with 5 and 6 cases, respectively); 10 of the 11 cases here would be Cluster KD cases, and 2 (occurring on Days 9 and 25) would be a Non-Cluster KD cases. The “Cluster Day” row indicates whether a given day in the time series falls within any 7-day window that contains at least 4 KD onsets. “Cluster KD Day” indicates a KD onset day defined as within a temporal cluster. These are the designations used in the construction of climate anomalies, and in all analyses grouped by temporal cluster membership (‘C’ indicate Cluster KD Days, and ‘NC’ indicate Non-Cluster KD Days). Although the initial definition is at least 5 KD case onsets in a period of 7 days, the final cluster length can extend beyond 7 days and final cluster size can extend beyond 5 cases, since a cluster is extended until a “break” occurs and there is a non-cluster day (e.g., Day 22). This is why the vertical axis of Fig. 2 refers to clusters greater than a given size.